I have a hardrock pro 05 with everything stock except the m540 pedals I put on it. I want to upgrade the front suspension because I don't like it. I need some suggestions on what type of suspension I should get for it under $450. Something lighter that wont cause me to loose as much speed when I try and sprint. Also what works better, spring, air, hydraulic?

I would get the fox vanilla r if I only had 450...

https://www.jensonusa.com/store/produ...6.aspx?sc=frgl

a vanilla sounds about right.

What type of riding do you do the most of? What do you not like about your current suspension?

Since you want to be able to sprint without the bob I would recommend something like this 2005 Rock Shox Reba Race Air w/ remote poplock (lockout). The poplock is extremely easy to use, I have it (the poplock) on one of my bikes and it works perfect. On top of that the fork is pretty light, weighs in around 3.5 pounds.

*edit* This fork is disc only. When I checked the specialized site the only 2005 Hardrock Pro I saw was disc.

Also check out the Reba.

I recently just got a Marz MX Pro. I am loving it. It is fairly light and very stable.

I do alot of urban riding during the week and then I hit the local bike trails on the weekend so I guess I do a little of everything with my bike. I realized after I purchased my bike that I will need to upgrade a lot of the components but oh well. I dont like the Marzocchi MZ Comp because it is not as smooth as I would like it too be. If I set it to lose then I bob and lose power when I sprint and if it is too stiff then well its too stiff.

the vanilla is plush and awesome... later you can get the compression and lockout internals when you get more money

So what is better coil or air preloaded?

air is lighter and more expensive

What exactly is a poplock feature? Besides weight and price, how do they compare with performance and maintenance?

Pop-loc is a remote lock out. It lets you lock out the fork by just using your thumb without taking your hands off of the bar. This is great for sprints or for less technical climbing.

As for how they compare I have a Rock Shox on one bike and the Fox on the other. They are both great for their intended purpose.

poplock is a lockout that runs from a cable to your handlebars... the fox vanilla has a lock out too but it doesn't have a remote (you probably dont really need a remote, but they have a cool factor )
check this out
https://www.mtbr.com/reviews/2005_front_shocks/

Actually once you have the remote lockout you realize how beneficial it really is. You use the lockout much more frequently than you use the lockout when it is located on the fork.

Personally I love Fox Forks, however I don't like their entry level forks at all. The ones I've tried I was never able to get set up "just right".